private Statements ParseStatements()
{
Statements statements = new Statements();
Statement st;
while ((st = this.ParseStatement()) != null)
{
statements.AddStatement(st);
}
return(statements);
}
public Program Parse(ArrayList <Token> tokens)
{
this.tokens = tokens;
Program prog = new Program();
Statements st = this.ParseStatements();
if (st != null)
{
prog.AddStatement(st);
}
return(prog);
}
public Function(string name, Statements inner, ArrayList <string> parameters, Expression returnValue)
{
this.Name = name;
this.Parameters = parameters;
this.innerStatements = inner;
}
// If then else
public Statement(StatementType type, Condition cond, Statements stat1, Statements stat2) : this(type, cond, stat1)
{
this.statements2 = stat2;
}
// If then, while
public Statement(StatementType type, Condition cond, Statements stat1) : this(type)
{
this.condition = cond;
this.statements1 = stat1;
}
public void AddStatement(Statements st)
{
this.statemets.AddRange(st.statemets);
}
private Function ParseFunction()
{
string name = "";
if (this.CurrentType == TokenType.ALPHANUMERIC)
{
name = this.Pop().Value;
}
if (this.CurrentType != TokenType.L_PAREN)
{
return(null);
}
this.Pop();
ArrayList <string> parameters = new ArrayList <string> ();
while (this.CurrentType == TokenType.ALPHANUMERIC)
{
parameters.Push(this.Pop().Value);
if (this.CurrentType == TokenType.COMMA)
{
this.Pop();
}
}
if (this.CurrentType != TokenType.R_PAREN)
{
return(null);
}
this.Pop();
if (this.CurrentType != TokenType.L_BRACE)
{
return(null);
}
this.Pop();
Statements st = this.ParseStatements();
Expression returnValue = null;
if (this.CurrentType == TokenType.RETURN)
{
this.Pop();
returnValue = this.ParseExpression();
if (this.CurrentType != TokenType.SEMI)
{
return(null);
}
this.Pop();
}
if (this.CurrentType != TokenType.R_BRACE)
{
return(null);
}
this.Pop();
return(new Function(name, st, parameters, returnValue));
}
private Statement ParseStatement()
{
while (this.CurrentType == TokenType.LINE_END)
{
this.Pop();
}
TokenType type = this.CurrentType;
if (type == TokenType.FUNCTION)
{
this.Pop();
Function fun = this.ParseFunction();
return(new Statement(StatementType.FUNCTION_DECLARATION, fun));
// If then, if then else
}
else if (type == TokenType.IF)
{
this.Pop();
Condition cnd = this.ParseCondition();
if (this.CurrentType != TokenType.L_BRACE)
{
return(null);
}
this.Pop();
Statements st1 = this.ParseStatements();
if (this.CurrentType != TokenType.R_BRACE)
{
return(null);
}
this.Pop();
if (this.CurrentType == TokenType.ELSE)
{
this.Pop();
if (this.CurrentType != TokenType.L_BRACE)
{
return(null);
}
this.Pop();
Statements st2 = this.ParseStatements();
if (this.CurrentType != TokenType.R_BRACE)
{
return(null);
}
this.Pop();
return(new Statement(StatementType.IF_THEN_ELSE, cnd, st1, st2));
}
else
{
return(new Statement(StatementType.IF_THEN, cnd, st1));
}
// while
}
else if (type == TokenType.WHILE)
{
this.Pop();
Condition cnd = this.ParseCondition();
if (this.CurrentType != TokenType.L_BRACE)
{
return(null);
}
this.Pop();
Statements st = this.ParseStatements();
if (this.CurrentType != TokenType.R_BRACE)
{
return(null);
}
this.Pop();
return(new Statement(StatementType.WHILE, cnd, st));
}
else if (type == TokenType.RETURN)
{
this.Pop();
Expression returnValue = this.ParseExpression();
if (this.CurrentType != TokenType.SEMI)
{
return(null);
}
this.Pop();
return(new Statement(StatementType.RETURN, returnValue));
// var, alphanumeric or alphanumeric ()
}
else
{
if (this.NextType != TokenType.L_PAREN)
{
Assignment asg = this.ParseAssignment();
if (asg == null)
{
return(null);
}
else
{
return(new Statement(StatementType.ASSIGN, asg));
};
}
else
{
Expression fun = this.ParseExpression();
if (fun == null)
{
return(null);
}
else
{
if (this.CurrentType != TokenType.SEMI)
{
return(null);
}
this.Pop();
return(new Statement(StatementType.FUNCTION, fun));
}
}
}
}
public void AddStatement(Statements stat)
{
this.statements.AddStatement(stat);
}
public Program(Statements statements)
{
this.statements = statements;
}
public Program()
{
this.statements = new Statements();
}
